Scientists boldly go where no man has gone before

Two human brains have been connected via the internet in an experiment which researchers compared to a Vulcan ''mind meld'' from Star Trek.

From his laboratory at the University of Washington, Rajesh Rao said he was able to control the hand movements of a colleague on the other side of campus using his thoughts. A cap filled with electrodes picked up signals from Professor Rao's brain and transmitted them via the internet to a magnetic coil on Andrea Stocco's head.

Rajesh Rao, left, plays a computer game with his mind. Across campus, researcher Andrea Stocco, right, wears a magnetic stimulation coil over the left motor cortex region of his brain. Stocco's right index finger moved involuntarily to hit the "fire" button as part of the first human brain-to-brain interface demonstration. Photo: University of Washington

As Professor Rao thought about tapping the space bar on his keyboard the coil stimulated Dr Stocco's left motor cortex, which governs hand movement, and prompted him to carry out the action. Studies have linked mouse brains, and amputees use similar technology to move robotic limbs, but the experiment is thought to be the first connection between people.

Dr Stocco said: ''The internet was a way to connect computers, and now it can be a way to connect brains. We want to take the knowledge of a brain and transmit it brain to brain.''

Tiny brains weighted with big expectations

Several of the hollow structures, which measure up to four millimetres across, were created as a model to help scientists learn what causes neurological disabilities.

Although researchers had previously grown slithers of brain tissue using stem cells, the new study was the first to create more complex 3D ''organoids'' which resemble the brain of a nine-week-old embryo.

Each one mimicked the layered structure of a developing brain, comprising defined regions such as a cerebral cortex and a forebrain.

They could not develop into a fully functioning brain, due in part to blood supply problems, but researchers – whose work was published in Nature – said the structures could be used to study how the brain develops and reveal the genetic causes of brain disorders and to study the effects of new drugs instead of using animals for testing.

The models were produced by putting the stem cells in a gel which allowed them to develop naturally then transferring them to a spinning bioreactor which encouraged them to grow.